[quote="Clicio" post=41531
The practical truth is that any potted plant can suffer, eventually die, in tropical sun.[/quote]

But this is canada. Hardly tropical, and similar latitude as e.a.g, central france.

leatherback wrote: But this is canada. Hardly tropical, and similar latitude as e.a.g, central france.

You are absolutely right.
In my mistful mind I was thinking California, in the summer, a closed balcony, no wind...
My mistake.
Being in Canada, full sun, of course.

We're not exactly cold... The past week we hit 30 degree highs and no rain.

The tree is in full sun for a full 12+ hours in my back yard on the north side.

When I say that the top half of the tree I mean literally the top half. I've attached a picture but it seems like scorching 12 hours of full sun is the most probable cause of the pines turning brown.

When I repotted the tree it looked a lot better like in my original post but after weekly fertilizing and full day's worth of sun it started to brown. I stopped fertilizing and even changed the soil in case there was something wrong with the soil. It's currently raining and the tree is looking slightly better (that picture was taken today) but I will continue to monitor it's colour.

Some folks here in Singapore use netting to reduce the harsh effects of midday sun. We are at 30-35 C throughout the year and junipers do just fine with some netting.

I could be wrong so someone please correct me if so but ...

This looks like it’s partially died back - you might not be able to stop it ... but stop messing with it .

You only repot healthy trees, fertilising a juniper weekly is gonna hurt the roots aswell. Good thing you stopped. Place in partial sun apply water .
But may be too late ... junipers react slowly. Was it rootbound? Did you cut any of the roots or leave any of the soil?

I don't remember cutting any roots the first time I repotted it in April. The tree was doing great but as the temperature rose the tree started Browning as well. If it were to die wouldn't it die from the bottom up? The lower portion of the tree still looks green which is confusion.

I didn't retain any of the old soil because it was so packed and drained very poorly. Both times I replaced the soil the roots were very healthy; no white roots anywhere.

It's my first bonsai tree so if it dies I'm not too worried about it. I was afraid it wouldn't last the winter because rain kept freezing in my area and at some point the pot was frozen solid to the roots when I left it outside. I had to leave it in my garage to defrost hoping the cold snap didn't kill the roots which was a miracle but now it seems like the heat is killing it instead.

What I'm wondering is how the nurseries are able to keep their bonsai so green and vibrant in a greenhouse when everywhere I read suggests it requires full sun.

When reporting Junipers - we usually try to keep a good portion of the rootball. Junipers don’t like being bare rooted, the reason why it is likely not responding well to full sun is because it can’t absorb water well. It’s like someone sowing your mouth up and leaving you in the sun.

This Juniper will most likely not make it, trees often die with new growth first, as it is weaker.

If you get a new juniper, try not to mess with it so much. It may of been fine with just partial shade and water.

Well lesson learned.

Strange thing is that it did great the first time I report it but after some extreme weather changes like cold snaps and extreme heat I assumed the sun killed it.

I'll just leave it be for now and hope it bounces back if not I'll know what to do next time around.

Everyone kills a tree every now and again, at least it was cheap!

Have patience with the next one
Junipers react quite slowly but stick to one major punishment a growing season if you can!

leatherback wrote: This is a clear case of sunbleech. You put the sun from a well-protected dark location into a sunny windy location and the leaves will burn up. Sometimes in as little as half an hour this damage may occur.

It does NOT mean the plantspecies cannot deal with direct sun. IT does mean you tried to make the transition too quick. Normally the transition from indoors to outdoors is made in a few phases, where you let the plant get use to the outdoors, by placing in a sheletered shaded position for a few days. THen allow some early or late day sun. And then into the full sun, but ideally on some cloudy days.

Damage is done. Now the plant has to throw out new leaves.

Just found that quote in another thread and I realized I did the exact same thing. Kept the damn thing inside and then brought it out during full sun and repotted it. I didn't transition or keep it in shade or anything. Could this have applied to my juniper?